Rangos: Single crystal probes: 2.25 MHz = 3.0 to 250mm 3.5 MHz = 2.0 to 150mm 5.0 MHz = 1.0 to 50mm Twin crystal probes in Single-Echo: 5.0 MHz = 2.0 to 100mm 2.0 MHz = 3.0 to 150mm Twin crystal probes in Echo-Echo: 5.0 MHz = 4.0 to 50mm 2.0 MHz = 6.0 to 50mm